The objective of this contract is to maintain the life cycle of Schistosoma mansoni for the Laboratory of Parasitic Diseases and provide investigators with different stages of the life cycle most commonly cerceriae and adult worms. The goals of this research include identification of relevant antigens of schistosomes including antigens responsible for the development of immunity in the mouse model and the identification of antigens or excretory- secretory products which would be useful clinically or to predict clinically important complications.